Pump



J. E. HALL Feb. 2, 1943.

PUMP

Filed Aug.v 5, 1939 2 Sheets-Sheet l A RNWY.

lf T 72 J. E. HALL Feb. 2, 1943.

PUMP

Filed Aug. 5.' 1939 2 Sheets-Sheet 2 Patented Feb. 2, 1943 PUMP Jesse E. Hall, Los Angeles, Calif., assigner, by di- .rect andvmesne assignments, to Pacific Pump Works, Huntington Park, Calif., a corporation of California Application August 5, 1939, Serial No. 288,629

(Cl. S-46) 6 Claims.

This invention is a pump, the present invention being a continuation in part of my cepending application Ser. No. 242,750, filed November 28, 1938.

It is an object of the invention to operate an actuator by fluid pressure, with the same conduit which supplies the pressure fluid providing for passage of this fluid to or from a pump which is operated by the actuator.

It is a further object of the invention to shift an actuator and a pump in one direction by fluid pressure, with said shifting of the actuator storing energy which upon relief of the fluid pressure shifts the actuator and the pump in the opposite direction.

It is a still further object of the invention to alternately exert and relieve lluid pressure upon the actuator for cyclic operation.

It is a still further object of the invention to exert iluid pressure at differential area of the actuator, for shifting the actuator in one direction against resistance at its minor-area working face, with said shifting of the actuator storing energy which upon relief of the uid pressure exerts pressure at the differential area for shifting the actuator and the pump in the opposite direction.

It i's a still further object of the invention to regulate exertion of fluid pressure and its a1- ternate relief, so that when exerted at the differential area of the actuator thefluid'pressure shifts the actuator in one direction against resistance at its minor-area working face, and stores such energy that upon relief of the uid pressure the stored energy which is then exerted at the differential area shifts the actuator and the pump in the opposite direction against resistance determined by the particular type of pump, and which resistance may be exerted throughout the minor-area Working face of the actuator.

It is a still further object of the invention to adapt the pump for coordination of its working stroke with either shifting of the actuator and the pump responsive to fluid pressure or with reverse shifting of the actuator and the Y pump responsive to stored energy.

More particularly it is an object of the invention to contract a compression chamber and compression chamber responsive to pressure of the compressed elastic fluid.

It is a still further object ofthe invention to seal the compression chamber to the substantially non-'compressible iluid throughout the major portion of contraction and expansion of said chamber; but at terminal contraction of the compression chamber to preferably open it to the substantially non-compressible uid in the event the pressure of said fluid exceeds that in the compression chamber, and at terminal expansion of the compression chamber to preferably discharge therefrom into the substantially non-compressible fluid in the event the pressure in the compression chamber exceeds that of the substantially non-compressible iluid.

The invention is particularly applicable to pumping fluid through a conduit, with the actu-V ator installed in the conduit adjacent the pump for direct connection therewith, and operated by alternately exerting and relieving pressure upon the iluid at a point `remote from the pump. Fluid may thus be pumped via the conduit and the uid in this same conduit provides means for transmitting energy for operating the pump from a source of power which may be at a point along the conduit remote from the actuator and the pump.

The invention is thus particularly applicable to well pumps. The pump and its actuator may be installed at any desired level in a well for pumping fluid via a usual well string, and at the earths surface pressure may be alternately exerted and relieved on this fluid in the Well string for operating the actuator and the pump.

Further objects of the invention will be readily -understood from the following description of the accompanying drawings which illustrate various forms which the invention may assume in practice, it being understood that the forms which are shown and described are for purpose of illustration, and that the invention may be modified and is entitled to various forms with.. out departing from the scope of the appended claims.

In the drawings:

Fig. 1 is a vertical section through control mechanism for the actuator, showing the upper end of a well string in which the actuator and pump are installed.

Fig. 2 is a vertical section through the lower endof the well string, showing the pump and apparatus which is operated thereby.

Fig. 3 is a detail vertical section through the upper portion of the actuator.

Fig, 4 is a transverse section on the line 4-4 of Fig. 3.

Fig. 5 is a detail vertical section through the lower portion of the pump and apparatus which is operated thereby.

Fig. 6 is a fragmentary view similar to Fig. 5, showing a modification of the pump which is operated by the actuator.

The invention is particularly applicable to an oil well pumpl which together with its actuator are installed at any desired level in a well. with means at the earths surface for alternately exerting and relieving pressure upon the column of fluid which is being pumped, and with this alternate exertion and relief of fluid pressure operating the actuator and the pump which is connected thereto. The actuator or iiuid motor for the pump is described and claimed in my copending application Ser. No. 335,291, filed May 15, 1940; the present invention being a pump actuated by such a fluid motor.

As an instance, a usual well string I extends from the earths surface into a well bore; and an actuator 2 is installed in the well string at any desired level, preferably immediately above the pump which is to be operated by the actuator.' The actuator is operated by alternately exerting and relieving pressure upon a column of fluid in the well string, there being means at the earths surface for controlling this alternate exertion and relief of pressure; and in addition to thus transmitting energy for operating the actuator, the column of fluid in the'well string may be fluid which is adapted for flow to or from the pump which is to be operated by the actuator.

For example, the single well string I carries the column of iluid which is being pumped, and this same column of fluid transmits energy for operating the actuator.

The actuator is shifted in one direction by pressure exerted upon the column of fluid in the well string I, with this shifting of the actuator storing energy which upon relief of pressure upon the column of uid shifts the actuator in the opposite direction. The stored energy is preferably pressure of an elastic iiuid, which is compressed by shifting the actuator responsive to pressure of the column of fluid.

As an instance of this arrangement, the upper end of the actuator is adapted for sealed sliding t in the bore of a liner 4 which is fixed in the well string I at any desired level, and the lower end of the actuator is of reduced diameter so that the actuator forms a shoulder 5 between its upper and lower ends, and the lower end of the actuator is adapted for sealed sliding t in the bore of a liner 8 which is fixed in the well string in spaced relation below the liner 4. The annular space 1 which surrounds the depending end of the -actuator between the shoulder 5 and the upper end of the liner 6 thus forms a chamber which is sealed at its ends by sliding fit of the ends of the actuator in the bores of the liners 4-6 and which is longitudinally contracted when the actuator is shifted downwardly, thereecmpressing fluid in the chamber 1.`

To increase the capacity of the compression chamber 1, the actuator preferably comprises a sleeve 8 and a concentric depending element 9 which is of smaller diameter than the sleeve; and the sleeve is closed at its upper end but is open at its lower end to the compression lchamber l via an annular space I8 which is formed between the element 9 and a surrounding collar 2| which depends from thef lower end of the sleeve 8 at the shoulder 5. The interior of the sleeve 8 thus forms a continuation la of the compression chamber 1.

The depending element 9 is connected to the pump which is to be operated by the actuator, and fluid in the well string above the liner 4- may flow to or from the pump via a bore which extends through the element 9, with the upper end of the bore opening through the wall of the sleeve 8 at; the upper portion of said sleeve which is ofreduced diameter as shown at II.

The actuator 2 and the pump 4which is suspended from the element 9 are adapted for limited reciprocation in the well string I. Down- Ward displacement of the actuator is limited by engagement of the shoulder 5 with the upper end of the liner 6, and upward displacement of the actuator is limited by engagement of a collar I2 on the element 9 with an annular shoulder I3 which is formed in a radially enlarged upper end 20 oi the bore of the liner 6.

The liner 6 is lowered into and withdrawn from the well string along with the actuator 2, the liner being suspended from the element 8 by engagement of its shoulder I3 with the collar I2; and when the liner is in place it may seat on a shoulder I4 of the well string with packing I5 preferably mounted between the upper end of the liner and the surrounding well string, and with the element 9 then adapted for reciprocation in the liner between the limits of reciproca.- tion as determined by the engagements 5 8 and I2--I3. The liner 6 may be anchored on the shoulder I4, preferably by usual anchoring means I 8 which when the liner has seated on the shoulder is automatically engaged, but which is adapted to yield responsive to a strong pull exerted on the actuator 2, for withdrawing the liner along with the actuator.

When the actuator 2 and the liner 6 have been operatively positioned in the well string, that portion of the Well string which is above the liner 4, and the annular space surrounding the diametrically reduced upper portion II of the sleeve 8, are lled with a substantially non-compressible fluid, with saidfiuid adapted for iiow via the bore of the element 9 to or from the pump which is suspended therefrom and which is to be operated by the actuator; and the annular space 'I together with the lower portion of the space 'la preferably also contains this substantially non-compressible fluid, while the upper portion of the space Ia con tains an elastic uid.

By a control at the earths surface, pressure is then exerted on the column of substantially noncompressible iiuid in the well string, with the sealed sliding fit of the sleeve 8 in the liner 8 preventing escape of this pressure past the actuator, and with means (hereinafter described) which is provided in the bore of the element 8 preventing escape of this pressure via said bore. The actuator 2 is thus shifted downwardly, thereby longitudinally contracting the compression chamber 'I-la and thus compressing the elastic fluid in the upper portion of the space la. The pressure on the column of fluid in the well string is then relieved, whereby pressure of the elastic fluid which has been compressed in the upper portion of the space 1a elevates the actuator, thereby longitudinally expanding. the compression chamber 1 1a. The cycle of operation is then repeated. and this reciprocation of the actuator operates the pump which is connected to its depending element 9.

Means are preferably provided for so compressing the elastic fluid during downstroke of the actuator, as to cushion and terminate the downstroke short of engagement of the shoulder with the upper end of the liner 6, with said compression of the elastic fluid providing pressure which is adequate to then elevate the actuator against whatever load resistance may be encountered. For ,this purpose. as the actuator approaches its limit of downward travel the pressure in the compression chamber 1--1a is automatically equalizedwith whatever pressure has been exerted on the substantially non-compressible uid for downwardly shifting the actuator. This equalization of pressure is preferably obtained by providing a passageway which is sealed throughout major portion of reciprocation of the actuator, but which opens the upper portion of the well string I to the compression chamber 11a as the actuator approaches its limit of downward travel.

As an instance of this arrangement, the sleeve 8 includes a section 26 at the lower end of its diametrically reduced portion II, with this section vaxially bored as shown at 21. The bore 21 terminates'short of the upper end of the section 26, and the element 9 depends from and communicates with the lower end of said bore. At its upper end, the bore 21 opens laterally through the Wall of the sleeve 8 at the lower end of its diametrically reduced upper portion Il as shown at 28.

The section 26 also has a series of longitudinal bores spaced circumferentially around the bore 21, with the bore 28 extending laterally between two of these circumferentially spaced bores as shown at Fig. 4. One of these longitudinal bores,

shown at 29, communicates at its lower end with a port 30 which opens laterally through the peripheral Wall of the sleeve 8 in spaced relation below its diametrically reduced upper portion Il; and the upper end of the bore 29 terminates short of the upper end of the section 26 and communicates laterally with an axial bore 3| which opens through the upper end of said section. A check valve at the upper end of the bore 3l opens for ow from said bore into that portion of the space 1a which is above the section 26, while closing against reverse flow from said space into said bore. The remainder of the longitudinal bores which are circumferentially spaced around y the bore 21 and which are shown at 32, communigates at their respective ends with the portions of the space 1a. which are respectively above and below the section 26.

The liner 4 has a radially enlarged bore intermediate of its ends as shown at 33, so that throughout major portion of reciprocation of the actuator 2 the port 30 is closed by the Wall of the bore of the liner 4, but as the actuator approaches terminal downward travel the port 30 alines with the enlarged bore 33 as shown at Fig. 3, thereby opening the port 30 to the annular space surrounding the diametrically reduced upper portion Ii of the sleeve 8. The substantially non-compressible uid which is in the upper portion of the well string, thus ilows via said annular space and the open port 30 and the bores 29-3I, past the check valve 25 and into the upper portion of the space 1a, and thence via the bores 32 and into the lower portion of the compression chamber- 'I-M, until the pressure of the elastic fluid which has been compressed in the upper portion of the compression chamber 1-1a equals that or the non-compressible fluid in the upper portion of the well string.

Any desired pressure may thus be exerted upon the column of substantially non-compressible fluid in the upper portion of the well string for insuring downward travel of the actuator: and any desired pressure may be built up in the lcompression chamber 1-1a by exerting desired pressure upon the column o1' substantially non-compressible iluid, so that upon relief of pressure of said column of iiuid, the pressure of the compressed elastic fluid -in the upper portion of the space 1a will upwardly shift the actuator 2 against any load resistance which may be encountered. During relief of pressure of the column of substantially non-compressible uid in the upper portion o! the well string, the check valve 25 closes'against escape of pressure from the compression chamber 1--1a.

Additional means are preferably provided for cushioning downstroke of the actuator in the event of such abnormal downward travel as to engage the shoulder l with the upper end of the liner 6. For this purpose, during normal downward travel of `the actuator for longitudinally contracting the compression chamber 1-1a, the collar 2| which depends from the ,lower end of the sleeve 8 remains clear of the upper end of the liner 6, and the non-compressible iluid in the space 1 is thus free to iiow via the annular space I0 into the space 1a for compressing the elastic iluid in' the upper portion of the space 1a. But in the event of abnormal downward travel of the actuator, the collar 2| snugly telescopes within an enlarged bore 2Ia at the upper end -of the liner 6, thereby restricting ilow via the annular space I0 and thus trapping substantially non-compressible fluid in the space 1 so as to cushion abutment of the shoulder 6 against the upper end ofthe liner 6.

Means are preferably provided for cushioning, and terminating upstroke of the actuator short of engagement of its collar I2 with the shoulder I3. For this purpose, when the pressure of the column of substantially non-compressible fluid in the well string has been relieved and as the j actuator approaches its limit of upward travel responsive to pressure of the elastic fluid which has been compressed in the upper portion of the space 1a, pressure of this elastic fluid is automatically equalized with that of the relieved pressureof the columnof fluid in the well string. Thus equalization of pressure is preferably obtained by providing a passageway which is sealed throughout major portion of reciprocation of the actuator, but which opens the compression' chamber 1-1a to the -upper portion of the well string I as the actuator approaches its limit of -rupward travel,

As an instance of this arrangement, a port 36 opens laterally from the bore of the element 9 and through the peripheral wall of said element, and the enlarged bore 2li of the liner 6 extends downwardly from the upper end of the liner to a level whereby throughout major portion of reciprocation of the actuator 2 the port 36 is closed by the wall of the bore of the lower portion of the liner 6, but as the actuator approaches terminal upward travel the port 36 alines with the enlarged bore 20 as shown at Fig. 5, thereby opening the port 36 to this enlarged bore. V

The enlarged bore 20 forms a continuation 1b of the compression chamber 1-1a; and when the port 36 is opened, the substantially non-compressible fluid which is in the lower portion of the compression chamber thus flows via said open port into the bore of the element 9 which communicates with the bore of the well string I, until the pressure of the elastic fluid which has been compressed in the upper portion of the space Ia is reduced to the relieved pressure of the column of fluid in the well string. During subsequent exertion of pressure upon the column of substantially non-compressible fluid in the well string and in the bore of the element 9, for

Y again downwardly shifting the actuator, a check valve closes to prevent escape of pressure of this substantially non-compressible fluid from the bore of the element 9 via the port 36.

This check valve may be mounted in the bore of the element 9 above the port 36, as shown at 35 in that embodiment of the invention which is illustrated at Fig. and wherein the pump which is operated by the actuator 2 is a pump for elevating fluid via the bore of the element 9 and thence via the well string to the earths surface, the check valve being adapted to open responsive to fluid pressure exerted upwardly through the bore of the element 9, and to close responsive to gravity and fluid pressure exerted downwardly via said bore.

In the modification of the invention illustrated at Fig. 6, the check valve is mounted in the lateral port which is formed in the peripheral wall of the element 9, this lateral port being shown at 38' and the check valve being shown at 35. This construction is employed where the pump which is to be operated by the actuator 2 is 'a pump adapted for flow of fluid downwardly through the well string and thence downwardly via the bore of the element 9, the check valve 36 permitting free flow via the bore of the element 9, and being adapted to open against tersion of a cooperating spring and responsive to fluid pressure in the annular space 1b, and to close responsive to tension of its spring and fluid pressure in the bore of the element 9.

Prior to installing the actuator and the pump in a well string, elastic fluid may be precharged to any desired pressure in the upper portion of the compression chamber 'I-Ia-lb. For this purpose, the upper end of the sleeve 8 comprises a chamber 8a. which is detachably connected to the main portion of the sleeve, and the lower end of the chamber 8a is closed by a partition 31, with a valve 38 in said partition normally opened bya spring 39 but adapted to close against escape of pressure from the space 'Ic which is formed by the chamber 8a. Prior to mounting the chamber 8a on the sleeve 8, the valve 38 is manually closed against the tension of its spring and elastic fluid is compressed in the space 1c, with the pressure of the compressed fluid maintaining the valve 38 in closed position. The elastic fluid may be supplied at desired pressure from any suitable source, via a supply duct 22 in the chamber 8a, which may `be provided with a check valve 23 and which after the desired pressure has been attained in the space 1c may be closed by an element 24 which provides means Whereby the actuator may be suspended from any suitable means (not shown) for lowering the actuator into and withdrawing it from the well string I.

The chamber 8a is then assembled on the sleeve 8 and the actuator and the pump are lowered into the well string I which is lled with a column of substantially non-compresslble fluid. As the actuator is lowered through this column of fluid, the hydrostatic head of the fluid column compresses the air which is trapped in the upper portion of the space 1a, and the precharge pressure in the space 'Ic is such that by the time the actuator reaches its operative position in the well string, the pressure in the upper portion of the space 1a, plus tension of the spring 39, opens the valve 38 and thus provides equalized precharge pressure in the upper portion of the space Ia and in the space 1c, with the spring 39 then retaining the valve 38 in open position throughout the cycle of operation and irrespective of surge of pressure past the open valve, so that the space 1c forms a continuation of the compression chamber L M-1b, with the pressure thus uniform through this ventire compression chamber.

The precharge pressure which is thus established throughout the entire compression chamber is preferably such that when the liner 6 has been seated on the shoulder I4 and the actuator is ready for reciprocation by alternately exerting and relieving pressure on the fluid column in the well string I, the actuator and the plunger of the pump are approximately balanced between the hydrostatic head of the column of fluid which tends to lower the actuator and pressure of the elastic fluid in the space 'Ia-1c which tends to elevate the actuator.

In order to adapt the pump for operation by the actuator, the lower end of the liner 6 may form a usual pump barrel 40 and the lower end of the element 9 may form a usual pump plunger 4I which is adapted for reciprocation in the barrel 40, with that portion of the well string I which extends below the pump comprising usual perforated pipe 42. The pump may force fluid into the well bore via the perforated pipe 42- or may withdraw uid from the well bore via said perforated pipe, i. e. the column of substantially non-compressible fluid in the well string I may be circulation fluid which is supplied to the upper end of the well string I and which it is desired to pump via the bore of the element 9 and thence via the perforated pipe 4I into the surrounding well bore, or it may be production fluid from the well which ls adapted for intake via the perforated pipe 42 and which is then pumped via the bore of the element 9 and the well string I for elevation to'the earths surface.

As shown at Fig. 5, the pump is adapted for pumping fluid from the well, e. g., production fluid such as oil, with which some quantity of gaseous constituents may be entrained. For this purpose, usual standing valves 43 are proy vided in the pump barrel 40 below the reciproeating plunger 4I, and usual working valves 44 are provided in the hollow bore of the plunger 4I which communicates with the hollow bore of the element 9. The valves 43--44 are adapted to open responsive to fluid pressure exerted upwardly via the bore of the pump, and to close responsive to gravity and fluid pressure exerted downwardly via the bore of the pump. When the pump plunger is reciprocated by the actuator 2, the pump is thus Vadapted for usual operation for elevating production fluid from the well via the bore of the element 9 and thence via the well string I to the earths surface, with the check valve 35 functioning as one of the working valves of the pump.

At-the modication which is shown at Fig. 6, the'pump is adapted for pumping lluid'into the well, e. g., a liquid medium such as usually employed for circulation in a well.. For this purpose, the standing valves 43' inthe pump barrel 48' and the working valves 44 in the plunger 4|' of the pump are adapted to open against tension of cooperating springs and responsive to fluid pressure exerted downwardly via the bore of the pump, and to close responsive to tension of their springs and iluid pressure exerted upwardly via the .bore of the pump. When the pump plunger is reciprocated by the actuator 2, the pump is thus adapted for .usual operation, i. e., flow of circulation iiuid downwardly through the well string I from thefearths surface and thence through the bore'of the element 8, from whence it is pumped into the surrounding well bore.

At the earths surface pressure is alternately exerted and relieved upon the column of substantially non-compressible fluid in the well string, i. e., the column of production liquid which is being pumped from the well (Fig. 5) or the column of circulation liquid which is being pumped into the well (Fig. 6). When pressure is thus exerted upon the column. of fluid it depresses the actuator 2 and the pump plunger 4I; and relief of this pressure permits elevation of the actuator and the pump plunger by pressure of the elastic fluid in the chamber 1a-1c, this elastic iiuid being preferably inltially precharged to desired pressure as previously described, and during downward movement of the actuator 2 being' further compressed by contraction of the compression chamber 1-1a 1b1c. V

The pressure which is exerted via the substantially non-compressible column of fluid for downward stroke of the actuator, is exerted downwardly against the upper end of the sleeve 8 (the diameter of which is dened by the liner 4), but the bore of the element 9 (the diameter of which is dened by the liner 6) opens through the actuator; and therefore the effective area against which pressure is exerted, is the area deilned by the diameter of the liner 4, less the area defined by the liner 8, i. e., the effective area is the differential area which is the dierence between the areas defined by the diameters of the liners 4 6. Upon relief of pressure exerted via the column of fluid in 4the well string, the compressed elastic uld in the chamber 1a-1c exerts pressure for upward stroke of the actuator. This pressure is exerted upwardly against the sleeve 8, but here again, due to the bore of the element 9 opening through the actuator, the effective area agalnst'which this pressure is exerted is the diil'erential area which is the diiference between the areas deiined by the diameters of the liners 4 8. The pressure exerted via the column of uld in the well string and its subsequent relief is such, that the pressure exerted lby the co1- umn of substantially non-fcompressible iiuid at said effective area, i. e. at said diilerential area will depress the actuator for compressing the elastic uid in the chamber 1a-1c to a pressure whereby upon relief of pressure of the column of substantially non-compressible fluid, the pressure of the elastic huid exerted at said effective area, i. e. at said dierential area will elevate the actuator and the pump plunger against hydrostatic head of the'column of iluid'in the well string. v

Means are provided at the earths surface for alternately exerting and relieving pressure upon the column of iiuid in the well string. While pressure is being exerted, additional fluid is sup- 5 plied to the column inaccordance with that increased capacity of the string which results from downward displacement of the actuator; and

' during relief of pressure, iluid is discharged at the earth's surface in accordance with that reduced capacity of the string which results from upward displacement of the actuator.

For this purpose, a valve 46 at the earths surface comprises 'a cylinder 41 in which a piston 48 is adapted for reciprocation, with the piston annularly recessed intermediate of its ends as shown at 49. A port 50 opens through the wall of the cylinder 41 for communication with the recess 48 throughout reciprocation of the piston, and ports 5|-52 open through the wall of the cylinder for respective communication with the recess 48 at opposite limits of travel of the piston. A conduit 53 connectsthe port 50 and the well string i; and conduits 54-55 respectively connect the ports 5I-52 with a source of uid under pressure and with storage for said uid, the iluid being the substantially non-compressible nui@ which illis the well string I and which is adapted for iiow to or from the pump which is to be operated by the actuator 2.

When the piston 48 is at its linut of travel as shown at Fig. 1, 'fluid under pressure is supplied to the well string via conduit 54, communicating ports -5I--5IIv and conduit 58, for depressing the actuator 2 and maintaining the well string filled to capacity during said displacement of the actuator. When predetermined pressure has been attained in the well string the piston 48 is shifted to its opposite limit of travel, thereby relieving pressure in the well string via conduit 53, communicating ports 50-52 and conduit 55. The actuator 2 is thus elevated by pressure of the compressed elastic fluid in the space 1a-1c, with iiuid from the weil string in excess of that reduced capacity of the string which results from upward displacement of the actuator, also discharging via conduit 58, communicating ports 5052 and conduit 55.

'I'he piston of the valve 46 may be positively shifted to its respective limits of travel, by iluid pressure which is alternately exerted against the respective ends of the piston, with corresponding relief of pressure at the opposite end of the piston; and the pressure for reciprocating the piston may be pressure of the uid which is supplied vla the conduit 54. For this purpose, a pilot valve 51 may control iluid pressure, and may comprise a bore 58 in which a plug 58 is adapted for reciprocation, with the plug annularly recessed as shown at 50-5I-62. Ports 63-84-55 open through the wall of the bore 58 for respective communication with the recesses BO-SI-SZ throughout reciprocation of the plug 59, and ports 65-51. open through the wall of the bore 58 for respective communication with the recess 5| at opposite limits of travel of the plug 59. The port 65 ls respectively closed and open to the recess B0 while said port is respectively open and closed to the recess 6|, and the port 61 is respectively closed and open to the recess 62 while said port is respectivelyy open and closed to the recess 5I.

Conduits 58-58-10 are connected to the respective ports 63-84-65, and conduits 1|-12 connect the ports 56-51 to respective ends of the valve '45. The conduit 69 is connected to the conduit 54, and the conduits 88.--10 are connected to the conduit 55.

When the plug 58 is at its limit of travel as shown at Fig. i, pressure is exerted via conduits 54-68, communicating ports 64-61 and conduit 12, for shifting the piston of the valve 46 to the position shown at Fig. 1, with pressure at the opposite end of the piston relieved via the conduit 1|, communicating ports 66--63 and conduits 68-55. Pressure is thus supplied via the valve 46 for building up pressure in 'the well string I. When predetermined pressure is attained in the well string, the plug 59 is shifted to its opposite limit of travel. Pressure is thus relieved via conduit 12, communicating ports 61-66 and conduits 10-65, and is exerted via conduits 54-69, communicating ports 64-66 and conduit 1| for shifting the piston of the valves 46 to its opposite limit of travel. Pressure in the well string is thus relieved via the valve 46. Upon relief of pressure in the well string, the plug 59 is again shifted to the position shown at Fig. 1, for repeating the cycle of operation.

Means are preferably provided for automatically Icontrolling reciprooation of the piston of the valve 46, for building up pressure of the column of uid in the well string until predetermined pressure is attained, then relieving said pressure, and then repeating the cycle of operation. In the illustrated embodiment, this automatic control is obtained by automatically controlling reciprocation of the plug 59 of the pilot valve 51. As an instance, the plug 59 remains in the position shown at Fig. 1, for building up pressure in the well string via the valve 46, until said pressure overcomes predetermined resistance. Said pressure then shifts the plug 59 to its opposite limit of travel for relieving pressure in the well string via the valve 46, with the plug 59 then remaining in said last mentioned position until predetermined relief of pressure in the well string, whereupon the plug 59 is returned to its position shown at Fig. 1, for repeating the cycle of operation.

For this purpose, a piston is fixed to the valve plug 59 and is adapted for reciprocation in a cylinder 16 of the pilot valve 51; and a valve 11 is fixed to the piston 15 and cooperates with a port 18 which is of appreciably smaller diameter than that of the piston 15. A spring 19, the tension of which may be adjusted at 80, resists shifting of the piston 15 and the plug 59 from the position shown at Fig. 1 and in which position the valve 11 closes the port 18; and a conduit 8| connects the port 18 and the conduit 53 which communicates with the well string I. A relief port 82 may communicate with that end of the cylinder 16 which has the port 18. A relief port 83 may be closed by the piston 15 when it is in its position shown at Fig. l; and when the piston is at its opposite limit of travel the port 83 is open to that end of the cylinder 16 which has the port 1.8. Conduits 84--85 may lead from the ports 82-89 to the conduit 55. A port 86, controlled by a needle valve- 81, may open to the atmosphere at that end of the cylinder 16 which is remote from the port 18.

With the piston 15 and the plug 59 in the posi,- tion shown at Fig. 1, rthe valve 11 closes the port 18. At this time the valve 46 is in position supplying fluid under pressure to the well string I for building up pressure in the well string. 'I'he spring 19 will have been adjusted to yield upon predetermined pressure in the well string, exerted via conduit 8| against the restricted area of the valve 11. Yielding of the spring unseats the valve 11, whereupon the predetermined pressure in the well string is exerted against the relatively large area of the piston 15 for shifting the piston Cil and the plug 59 to their opposite limit of travel, thereby operating the valve 46 for reducing pressure in the well string I. After relief of pressure has been inaugurated, the piston 16 and the plug 59 remain in their last mentioned shifted position until pressure in the well string isso reduced that pressure via conduit 8| against the relatively large area of' the piston 15 is overcome by the tension of the spring 19. The piston 1.5 and the plug 59 are then returned by the spring 19 to the position shown at Fig. 1, thereby operating the valve 46 for again supplying fluid pressure to the well string for repeating the cycle of operation.

Any suitable means, indicated as a pump 99, may be employed for supplying uid under pressure to the conduit 64, the outlet of the pump being connected to the conduit 54 and the intake to the pump communicating with storage means 9| into which the conduit 55 discharges. Fluid is thus pumped from storage 9| into the well string for exerting any desired pressure therein, and is alternately discharged from the Well string to said storage for relieving pressure in the well string, with this alternate exertion and relief of fluid pressure reciprocating the actuator 2, and with the fluid in the well string owing via the bore of the element 9 to or from the pump which is operated by the actuator 2.

'I'he invention thus provides for transmitting energy for operating an actuator, and for flow to or from a pump which is operated by the actuator, via the same conduit; and also provides for transmitting the energy and supplying or discharging the uid from a point along the conduit which is remote from the actuator. The invention also provides for transmitting energy for shifting the actuator in one direction, with said shifting of the actuator storing energy for then shifting the actuator in the opposite direction, and with said shifting of the actuator in either direction forming its working stroke.

The actuator and the pump are shifted in the same direction at the same time.

Thus, when the pump is a lift pump (Fig. 5), the pressure exerted via the column of fluid in the well string shifts the actuator and the pump plunger downwardly for filling stroke of the pump. Upon relief of pressure of the column of iiuid the compressed elastic fluid in the compression chamber shifts the actuator and the pump plunger upwardly for discharge stroke of the pump. Therefore, throughout the entire length of the column of fluid, from the pump plunger to the earths surface, relief of pressure via the control at the earths surface is in the direction of elevation of fluid by the pump, thereby aiding in the pumping operation.

Furthermore, when the pump is a lift pump for an oil well, the column of fluid in the well string will be a column of oil which is substantially non-compressible for exerting desired pressure on the actuator during the filling stroke of the pump, but which will have some slight inherent elasticity due to the presence of gaseous constituents. Therefore, there will be some slight compression of the column of oil `(during the filling stroke of the pump), and upon relief of pressure on the column of oil (for discharge stroke of the pump) there will be some expansion of the column of oil; and throughout the entire length of the column of oil, from the pump plunger to the earths surface, this expansion will be in the direction of relief of pressure at the earths surface, i. e., it will be in the direction of elevation of oil by the pump and will thus aid in the pumping operation.

When the p ump is a force pumpc (Fig. 6) for forcing circulation fluid into a well, the pressure exerted on the column of uid ln the well string for downward stroke of the actuator and the pump plunger, i. e., the working stroke of thev pump, is exerted in the direction of said working stroke, throughout the entire length of the column of fluid, from the earths surface to the pump plunger, thereby aiding the pumping operation. In similar manner, during relief of pres-'- sure in the well string (for upward stroke of the pump), relief of pressure is in the direction of said upward stroke, throughout the entire length of the well string, from the pump plunger to the earths surface, thereby aiding in said upward stroke of the pump plunger.

I claim:

' 1. -In an oil well pump, a well string, a pair of j liners longitudinally spaced in the well string and having bores of different diameter, a `sleeve closed at its upper end and adapted for sealed sliding t in the liner of larger diameter, a tube depending from the sleeve, the upper end of the tube being open to the bore of the well string above the sleeve. the lower end of the tube being adapted for sealed sliding it in the liner of smaller diameter, a pump barrel suspended from the liner of smaller diameter and communicating at its lower end with a production zone of the well, a pump plunger suspended from the tube and adapted for sealed sliding t in the pump barrel, the pump plunger having a bore communicating with the tube, a, check valve in the bore of the pump plunger adapted to open responsive to pressure exerted upwardly via the bore of the pump plunger, a compression chamber for elastic fluid in the bore of the sleeve, said chamber having an extension thereof radially defined between the tube and the liner of larger diameter, the compression chamber being closed at its end bythe liner of smaller diameter and the 4closed upper end of the sleeve, and a control at the earths surface for alternately supplying production fluid to and discharging production fluid from the Well string for alternately exerting and relieving pressure on a column of production iiuid in the well string, whereby pressure of said column of uid is exerted against the upper surface of the closed upper end of the sleeve for downwardly shifting the sleeve and its depending tube and the pump plunger so as to contract the compression chamber and compress elastic fluid therein, and upon relief of pressure of said column of fluid the compressed elastic uid exerts pressure against the under surface of the closed upper end of the sleeve for upwardly shifting the sleeve and its depending tube and the pump plunger so as to expand the compression chamber. i

2. In a well pump, a well string, a pair of liners longitudinally spaced in the well string and having bores of different diameter, a sleeve closed at its upper end and adapted for sealed sliding nt in the liner of larger diameter, a tube depending from the sleeve, the upper end of the tube being open to the bore of the well string above the sleeve, the lower end of the tube being adapted for sealed sliding i'lt in the liner of smaller diameter, a pump barrel suspended from the liner of smaller diameter and communicating at its lower end with the bore of the well, a pump plunger suspended from the tube and adapted for sealed sliding fit in the pump barrel, the

pump plunger having a bore communicating with the tube. a check valve in the bore of the pump plunger,va compression chamber for elastic fiuid in the bore of the sleeve, said chamber having an extension thereof radially dened between the tube and the liner of larger diameter, the compression chamber being closed at its end by the liner of smaller diameter and the closed upper end of the sleeve, and a control at the earths surface'for alternately supplying uid to and discharging uid from the well string for alternately exerting and relieving pressure on a column of fluid in the well string, whereby pressure of said column of fluid is exerted against the upper surface of the closed upper end of the sleeve for downwardly shifting the sleeve and its depending tube and the pump plunger so as to contract the lcompression chamber and compress elastic uld therein, and upon relief of pressure of said column of fluid the compressed elastic fluid exerts pressure against the under surface of the closed upper end of the sleeve for upwardly shifting the sleeve and its depending tube and the pump plunger so as to expand the compression chamber.

3. In a pump, a conduit, a liner in the conduit, a. cooperating plunger, a compression chamber for elastic uid dened and closed to the bore of the conduit-by the 'cooperating liner and plunger, control means at one end of the conduit for alternately exerting and relieving uid pressure in the conduit, the cooperating plunger and liner being arranged whereby fluid pressure in the conduit shifts the plunger in direction away from the control end of the conduit for contracting y thecompression chamber and compressing elastic fluid therein, and upon relief of fluid pressure in the conduit the compressed elastic fluid shifts` the plunger in the opposite direction, a pump barrel at the end of the conduit remote from the control means, and a plunger for the pump barrel mechanically connected to and reciprocating with the first mentioned plunger and having a pump-valve controlling communication between the pump barrel and the bore of the conduit.

4. In a pump, a conduit, a liner in the conduit, a cooperating plunger, a compression chamber for elastic fluid defined and normally closed to the bore of the conduit by the cooperating liner and plunger,. control means at one end of the conduit for alternately exerting and relieving fluid pressure in the conduit, the cooperating plunger and liner being arranged whereby ud pressure in the conduit shifts the plunger for contracting the compression chamber and compressing elastic fluid therein, and upon relief of fluid pressure in the conduit the compressed elastic fluid shifts the plunger in the opposite direction, a passageway providing communication between the bore of thel conduit and the compression chamber at terminal shifting of the plunger, means permitting now via the passageway in only one direction, a pump barrel at the end of the conduit remote from the control means, and a plunger for the pump barrel mechanically connected to and reciprocating with the first mentioned plunger and having 4a pump-valve controlling communication between the pump barrel and the bore of the conduit.

5. In a pump, a conduit, a liner in the conduit, a cooperating plunger, a compression chamber for `elastic fluid defined and normally closed to the bore of the conduit by the cooperating liner and plunger, control means at one end of the conduit for alternately exerting and relieving fluid pressure in the conduit, the cooperating plunger and liner being arranged whereby uid pressure in the conduit shifts the plunger for contracting the compression chamber and compressing elastic iluid therein, and upon relief of fluid pressure in the conduit the compressed elastic iluid shifts the plunger in the opposite direction, passageways respectively providing communication between the bore of the conduit and the compression chamber at terminal shifting of the plunger in opposite directions, means permitting flow via each passageway in only one direction, a pump barrel at the end of the conduit remote from the control means, and a plunger for the pump barrel mechanically connected to and reciprocating with the rst mentioned plunger and having a pump-valve controlling communication between the pump barrel and the bore of the conduit.

6. In a pump, a conduit, a liner in the conduit, a cooperating plunger, a compression chamber for elastic fiuid deilned and closed to the bore of the conduit by the cooperating liner and plunger,

control means at one end of the conduit for alternately exerting and relieving fluid pressure in the conduit, the cooperating plunger and liner being arranged whereby fluid pressure in the conduit shifts the plunger for contracting the compression chamber and compressing elastic uid therein, and upon relief of iluid pressure in the conduit the compressed elastic fluid shifts the.

plunger in the opposite direction, an auxiliary chamber, means for precharging the auxiliary chamber with fluid under pressure, a valve controlling communication between the auxiliary chamber and the compression chamber and tending to open and close respectively responsive to pressure in the compression chamber and in the auxiliary chamber, a pump barrel at the end of the conduit remote from the control means, and a plunger for the pump barrel mechanically connected to and reciprocating with the ilrst mentioned plunger and having a pump-valve controlling communication between the pump barrel and the bore of the conduit.

JESSE E. HALL. 

